A can body maker apparatus is disclosed in U.S. Pat. No. 3,696,659, issued to J. H. Maytag and an improvement to the ram assembly of the can body maker ram assembly is disclosed in U.S. Pat. No. 4,934,169, issued to C. M. Grimes, et al Both of these patents which are assigned to Adolph Coors Company are incorporated herein by reference as if fully set forth.
Can body makers produce elongated can bodies from can shells at a rate of approximately 200 can bodies per minute. The can shells have a wall thickness of approximately 0.009 to 0.012 inch, and the elongated can bodies have a wall thickness of approximately 0.0045 inch. In a can body maker apparatus, as generally shown in the Maytag patent, a ram is movably mounted for reciprocal, straight line motion at rates sufficient to form from between 180 and 220 can bodies per minute. The stroke length, that is the distance traveled by the movable ram, is between about 18 to 26 inches. As a general rule, for a given can body maker, the shorter the ram stroke, the greater the rate or number of cycles per minute at which the ram can be operated. Misalignment as small as between about 0.0005 and 0.0010 inch can result in the formation of defective cans. The high speed, constant reciprocating movement of the ram assembly of a can body maker at up to 11,000 pounds of force creates extreme load magnitudes within the machine itself as well as in the floor on which the machine is mounted, not to mention the surrounding manufacturing facility. Such extreme load magnitudes create high levels of vibrations and contribute to the wear of all moving components within the machine.
As a result of the vibration generated by the ram assembly, efforts in the industry have been directed to developing new techniques for maintaining the ram assembly in alignment relative to the dies used to form the can bodies. As illustrated in the patents referenced above, ram carriage assemblies which were mounted for reciprocal movement on track and wheel arrangements typically have been replaced with fluid bearing support structures to minimize misalignment of the ram relative to the can body maker dies. Nonetheless, while alignment of the ram relative to the die is maintained within acceptable tolerances, the high speed reciprocal motion at rates of approximately 200 cycles per minute continues to generate extreme vibrations within the frame structure of the body maker apparatus as well as in the area surrounding the body maker.